KR100294498B1 - Electron gun of CRT - Google Patents

Abstract

Disclosed is an electron gun of a cathode ray tube in which the shapes of a focus electrode and an anode electrode forming a large-diameter lens are improved. The electron gun includes a cathode, a control electrode, and a screen electrode forming a three-pole portion, and a focus electrode and an anode electrode sequentially provided from the screen electrode, and the focus electrode and the anode electrode are mutually formed such that a large-diameter lens is formed therebetween. An outer electrode having a large diameter common electron beam through hole formed on an opposing surface, and a plate-shaped inner electrode respectively coupled to the inside of the outer electrode and having three small diameter independent electron beam through holes provided therein; When the electron beam through-hole piercing processing of the internal electrode is carried out, the direction opposite to the surface facing the punch faces the large-diameter lens.

Description

Electron gun of cathode ray tube {Electron gun of CRT}

The present invention relates to an electron gun of a cathode ray tube, and more particularly, to an electron gun of a cathode ray tube having improved shapes of an internal electrode of a focus electrode and an anode electrode forming a large diameter lens.

In general, as shown in FIG. 1, the electron gun of the cathode ray tube is applied to a prefocus lens P in which each electron beam L emitted from the cathode 1 is formed between the control electrode 2 and the screen electrode 3. After pre-focusing, the light is focused and accelerated by the main lens M formed between the focus electrode 4 and the anode electrode 5 to penetrate the holes of the shadow mask (not shown), and then a fluorescent surface (not shown). When the phosphor reaches and emits light, the smaller the diameter of the electron beam that reaches the phosphor surface, that is, the size of the imaging point, the better the focus characteristic, and the clearer the image.

However, since the in-line electron guns arranged in parallel in the same plane to emit electron beams have a monotonous dislocation distribution and a large incident angle of the projected electron beams, spherical aberration is also increased, thereby deteriorating focus characteristics and degrading resolution.

In order to solve this problem, a method of forming a common large-diameter lens in the main lens portion is used. That is, as shown in FIG. 2, the focus electrode 10 includes an external electrode 11 having a large-diameter electron beam passing hole 11a and three independent small-diameter electron beams provided inside the external electrode 11. The internal electrode 12 is formed with a through hole 12a. Although not shown, the anode electrode is formed of an external electrode and an internal electrode in the same manner as the focus electrode 10, and is provided to face the focus electrode 10.

In this case, a press work is performed to form the electron beam through hole 12a of the internal electrode 12. By this press process, a burr 12b is formed on one surface of the electron beam through hole 12a of the internal electrode 12. a burr is formed, and on the opposite side, a so-called edge radius 12c is formed in which the material is pushed inward. In the electrode of the conventional electron gun as shown, in order to prevent the potential from being concentrated on the burr 12b, the burr 12b of the internal electrode 12 faces the opposite direction of the large-diameter lens forming portion. Inserted into the joint. In this case, however, the surface of the inner electrode 12 facing the large-diameter lens forming portion of the electron beam passing hole 12a is positioned so that the edge radius 12c is not positioned so that the edge thereof is not exactly perpendicular to each other. This can increase the risk of lens distortion.

The present invention has been made to solve the above problems, and an object of the present invention is to provide an electron gun of a cathode ray tube having an auxiliary lens of a shape suitable for generating an accurate and reliable potential distribution.

1 is a schematic configuration diagram of an example of a conventional cathode ray tube electron gun,

2 is a sectional view of principal parts of an electrode of another example of a conventional cathode ray tube electron gun;

3 is a schematic cross-sectional view of an embodiment of a cathode ray tube electron gun according to the present invention;

4A to 4C illustrate a process of making an electrode of the electron gun of FIG. 3.

4A and 4B sequentially illustrate a process of piercing a material to form electron beam through holes of an internal electrode,

4C is a perspective view illustrating a state in which an inner electrode is coupled to an outer electrode.

Explanation of symbols on the main parts of the drawing

22 Cathode 23 Control electrode

24 ... screen electrode 30 ... focus electrode

40.Anode ... 31,41 ... External electrode

32, 42 Internal electrodes 101 Punch

103 ... die

The electron gun of the cathode ray tube of the present invention for achieving the above object is provided with a cathode, a control electrode and a screen electrode to form a triode, and a focus electrode and an anode electrode sequentially installed from the screen electrode,

The focus electrode and the anode electrode each have an external electrode having a large diameter common electron beam passing hole formed on a surface facing each other such that a large diameter lens is formed therebetween, and three independent small independent electron beam passing through the inside of the external electrode. A plate-shaped internal electrode provided with a ball,

The coupling direction of each of the internal electrodes is oriented so that the surface facing the punch faces the large-diameter lens in the electron beam through hole piercing process of the internal electrode.

In the electron beam through hole piercing processing of the internal electrode, the surface facing the punch is preferably pickled.

Hereinafter, with reference to the accompanying drawings, a preferred embodiment of the cathode ray tube electron gun according to the present invention will be described in detail.

As shown in FIG. 3, the electron gun of the cathode ray tube according to the present embodiment includes a cathode 22, a control electrode 23, a screen electrode 24, a focus electrode 30 constituting a main lens, and a cathode. It comprises an anode electrode 40 installed oppositely. Here, three cathodes 22 are arranged inline, and each of the electrodes arranged from the cathode 22 is formed with three electron beam through holes in-line.

In the electron gun for the conventional color cathode ray tube configured as described above, the focus electrode denoted by reference numeral 30 and the anode electrode denoted by reference numeral 40 are each composed of an internal electrode and an external electrode, thereby forming a large-diameter lens.

That is, as can be seen in the drawing, the focus electrode 30 includes a left outer electrode 33, a right outer electrode 31 coupled to the left outer electrode 33, and an inside of the right outer electrode 31. It is provided with a plate-shaped internal electrode 32 installed in. A large-diameter electron beam through hole 31a through which R, G, and B electron beams pass through is formed in the right external electrode 31, and each of the three electron beams exclusively passes through the plate-shaped inner electrode 32, respectively. Three independent electron beam through holes 32a are provided.

The anode electrode 40 also includes an external electrode 41 and a plate-shaped inner electrode 42 provided inside the outer electrode 41. The outer electrode 41 has a large-diameter electron beam passing therethrough. One hole 41a is formed, and the internal electrode 42 is provided with three electron beam through holes 42a of small diameter.

A large-diameter lens is formed between the electron beam through hole 31a of the external electrode 31 of the focus electrode 30 and the electron beam through hole 41a of the external electrode 41 of the anode 40.

The plate-shaped inner electrodes 32 and 42 of the focus electrode 30 and the anode electrode 40 continuously blank a material provided in the form of a strip by using a progressive mold or the like, and the electron beam through hole It forms through the process of piercing (32a, 42a).

In particular, in the piercing process, as shown in Fig. 4A, the plate-like material 105 blanked in a predetermined shape is fixed to the die 103 of the press machine and the punch 101 is moved downward, thereby causing electron beams to the material. Form a through hole. The product 105 produced by this piercing process (ie, internal electrodes 32 and 42) has typical characteristics that appear in the pressed workpiece. That is, as shown in FIG. 4B, the material surrounding the electron beam through hole is pushed to the surface X facing the upper side during the process of the internal electrodes 32 and 42, that is, the surface X toward the punch 101 of the press. The edge radius portions 32b and 42b are formed, and burrs 32c and 42c are formed on the surface opposite to the surface X, that is, the surface Y facing the die 103 during the process.

In addition, in order to remove the burrs 32c and 42c of the pierced internal electrodes 32 and 42, it is preferable that the surfaces on which the burrs 32c and 42c are formed are pickled using sulfuric acid or the like.

The internal electrodes 32 and 42 of the focus electrode 30 and the anode electrode 40 processed as described above are shown in Fig. 4C. The external electrodes 31 and 41 are inserted into the external electrodes and are coupled to predetermined positions by welding or the like. At this time, the coupling direction of the inner electrodes 32 and 42 is inserted and coupled with the Y surface facing the large-diameter electron beam passing holes 31a and 41a of the outer electrodes 31 and 41.

As shown in FIG. 3, the focus electrode 30 and the anode electrode 40 that are combined and completed in this manner are formed on the surface on which the edge radii 32b and 42b of each of the internal electrodes 32 and 42 are formed. X) faces the opposite side of the large-diameter lens forming portion, and the surface Y opposite thereto is positioned toward the large-diameter lens forming portion. The edge of the formation is almost perpendicular. In other words, the cross-sectional shape of the small-diameter electron beam passing holes 32a and 42a can be precisely formed on the surface Y close to the large-diameter lens, which is a surface that greatly affects the main lens potential in the auxiliary lenses 32 and 42.

As described above, the cathode ray tube electron gun according to the present invention can be precisely formed in the shape of the electron beam through hole of the internal electrode, thereby obtaining an electric potential distribution having a desired shape, thereby minimizing distortion of the lens. .

Although the present invention has been described with reference to one embodiment shown in the accompanying drawings, this is merely exemplary, and it will be understood by those skilled in the art that various modifications and equivalent other embodiments are possible therefrom. Could be. Therefore, the true scope of protection of the present invention should be defined by the appended claims.

Claims (2)

It comprises a cathode, a control electrode and a screen electrode for forming a three-pole portion, and a focus electrode and an anode electrode sequentially provided from the screen electrode, The focus electrode and the anode electrode, External electrodes each having a large diameter common electron beam through hole formed on opposite surfaces to form a large diameter lens therebetween; In the electron gun of the cathode ray tube coupled to the inside of the outer electrode and provided with a plate-shaped inner electrode provided with three small diameter independent electron beam through hole, The electron gun of the cathode ray tube, wherein the coupling direction of each of the internal electrodes is oriented so that the surface facing the punch faces the large-diameter lens in the electron beam through hole piercing process of the internal electrode. The method of claim 1, The electron gun of the cathode ray tube, characterized in that the surface facing the punch during the electron beam through hole piercing processing of the internal electrode is pickled.